I. Field
The following description relates generally to communications systems, and more particularly to reducing impact of saturation given a peak to average power ratio constraint.
II. Background
Wireless networking systems have become a prevalent means to communicate with others worldwide. Wireless communication devices, such as cellular telephones, personal digital assistants, and the like have become smaller and more powerful in order to meet consumer needs and to improve portability and convenience. Consumers have become dependent upon these devices, demanding reliable service, expanded areas of coverage, additional services (e.g., web browsing capabilities), and continued reduction in size and cost of such devices.
A typical wireless communication network (e.g., employing frequency, time, and code division techniques) includes one or more base stations that provides coverage areas to subscribers as well as mobile (e.g., wireless) devices that can transmit and receive data within the coverage areas. A typical base station can simultaneously transmit multiple data streams to multiple devices for broadcast, multicast, and/or unicast services, wherein a data stream is a stream of data that can be of independent reception interest to a user device. A user device within the coverage area of that base station can be interested in receiving one, more than one or all the data streams carried by the composite stream. Likewise, a user device can transmit data to the base station or another user device.
Forward Link Only (FLO) technology has been developed by an industry group of wireless communication service providers to utilize the latest advances in system design to achieve the highest-quality performance. FLO technology is intended for a mobile multimedia environment and is suited for use with mobile user devices. FLO technology is designed to achieve high quality reception, both for real-time (streaming) content and other data services. FLO technology can provide robust mobile performance and high capacity without compromising power consumption. In addition, the technology reduces the network cost of delivering multimedia content by decreasing the number of base station transmitters that are necessarily deployed. Furthermore, FLO technology based multimedia multicasting is complimentary to wireless operators' cellular network data and voice services, as cellular network data can be delivered to a same device that receives multimedia content by way of FLO technology.
Performance of transmitters, both within base stations and mobile devices, is crucial to success of a wireless system generally and in connection with FLO technology in particular. Additionally, as alluded to above, it is desirable to maintain low costs with respect to transmitters within wireless systems. Accordingly, mobile device manufacturers and wireless service providers want to limit peak to average power ratio (ratio of a peak power level to a time-averaged power level) at a transmitter without substantially degrading performance of such transmitter, thereby reducing size and cost of transmitters. In particular, if there is a high peak to average ratio with respect to a transmitter, a power amplifier therein must be linear over a wider range, resulting in larger, more expensive power amplifiers that require additional space to dissipate heat.